6 Cost of Dark Fermentative H 2 Production from Industrial
Waste
Environmental and economic parameters measure the sustainability of industrial
wastewater treatment. In this respect, the sustainability of producing H 2 as a clean
and renewable biofuel from industrial waste depends on the cost of the infrastructures, input materials (substrate, inoculum, nutrients, and chemicals), and the operation. Industrial waste from food processing facilities is a renewable source of
low-cost organics that can be converted to H 2 at low production costs. There are
some management and operation opportunities which could help reduce the cost of
H 2 production from industrial waste. For example, co-fermenting different wastes
lowers the production cost. In this case, the major substrate provides the carbon
source, the second substrate provides the nutrients required for the growth of
microorganisms, and the third substrate provides the required buffering capacity
and/or adjusts the pH. Such integration of co-substrate is economically crucial
because, for example, chemicals required to adjust the pH during dark fermentative
H 2 production formed 48.3% of the overall cost [229].
Limited information is available in the accessible literature on the economic
aspects of dark fermentative H 2 from industrial waste. A few studies [229, 240–
242] discussed the economic aspects of dark fermentative H 2 production briefly. The
H 2 production cost (USD/m
3 ) through dark fermentation of waste has been estimated
theoretically for beverage wastewater (7100), agriculture waste (7900), solid
biowaste (1.52), sugarcane distillery effluent (35.4), and kitchen waste (0.1–0.12)
[243–245]. Although the H 2 production cost from beverage and agriculture waste is
high, marginal net revenue has been estimated. Sugarcane distillery effluent and
solid biowaste generated higher estimated revenue. The type of reactor affects the
rate of H 2 production, which in turn affects the capital and operational cost
[246]. Molasses-based production of dark fermentative H 2 was estimated to cost
$9.52 per GJ [247], and it seems very competitive to gasoline ($22.28 per GJ) and
ethanol (€22.6 per GJ) [241]. The capital cost of the dark fermentative reactors
represented around 35.4% [242], which could be lowered by modifying conventional anaerobic digesters that treat industrial waste to produce H 2 instead of CH 4 .
An important factor that should be included in the cost estimate is that H 2 fermentation is not complete treatment because it discharges an effluent concentrated with
VFAs which requires further treatment. Obviously, VFA-rich liquid waste is suitable
for CH 4 production using the conventional anaerobic digestion. Therefore, a
two-stage process could be configured to enable sequential extraction of energy
from industrial waste.
8 Biohydrogen of Industrial Waste
355
Waste
Environmental and economic parameters measure the sustainability of industrial
wastewater treatment. In this respect, the sustainability of producing H 2 as a clean
and renewable biofuel from industrial waste depends on the cost of the infrastructures, input materials (substrate, inoculum, nutrients, and chemicals), and the operation. Industrial waste from food processing facilities is a renewable source of
low-cost organics that can be converted to H 2 at low production costs. There are
some management and operation opportunities which could help reduce the cost of
H 2 production from industrial waste. For example, co-fermenting different wastes
lowers the production cost. In this case, the major substrate provides the carbon
source, the second substrate provides the nutrients required for the growth of
microorganisms, and the third substrate provides the required buffering capacity
and/or adjusts the pH. Such integration of co-substrate is economically crucial
because, for example, chemicals required to adjust the pH during dark fermentative
H 2 production formed 48.3% of the overall cost [229].
Limited information is available in the accessible literature on the economic
aspects of dark fermentative H 2 from industrial waste. A few studies [229, 240–
242] discussed the economic aspects of dark fermentative H 2 production briefly. The
H 2 production cost (USD/m
3 ) through dark fermentation of waste has been estimated
theoretically for beverage wastewater (7100), agriculture waste (7900), solid
biowaste (1.52), sugarcane distillery effluent (35.4), and kitchen waste (0.1–0.12)
[243–245]. Although the H 2 production cost from beverage and agriculture waste is
high, marginal net revenue has been estimated. Sugarcane distillery effluent and
solid biowaste generated higher estimated revenue. The type of reactor affects the
rate of H 2 production, which in turn affects the capital and operational cost
[246]. Molasses-based production of dark fermentative H 2 was estimated to cost
$9.52 per GJ [247], and it seems very competitive to gasoline ($22.28 per GJ) and
ethanol (€22.6 per GJ) [241]. The capital cost of the dark fermentative reactors
represented around 35.4% [242], which could be lowered by modifying conventional anaerobic digesters that treat industrial waste to produce H 2 instead of CH 4 .
An important factor that should be included in the cost estimate is that H 2 fermentation is not complete treatment because it discharges an effluent concentrated with
VFAs which requires further treatment. Obviously, VFA-rich liquid waste is suitable
for CH 4 production using the conventional anaerobic digestion. Therefore, a
two-stage process could be configured to enable sequential extraction of energy
from industrial waste.
8 Biohydrogen of Industrial Waste
355